textproduct: Rapid City

KEY MESSAGES

- Thunderstorms may develop over the area this afternoon and again Sunday afternoon. Some storms may become strong to severe and produce damaging wind gusts.

- Very warm weather with daily chances for afternoon storms continues into next week.

- Near-critical fire weather concerns continue into early next week, mainly over northeastern WY into southwestern SD.

DISCUSSION

(This Afternoon Through Friday) Issued at 1105 AM MDT Sat Aug 29 2026

Upper level analysis depicts upper trof making its way onshore into the PNW with broad ridging over the central US. The Northern Plains sits under southwest flow with water vapor imaging showing a few weak waves and convection over the Rockies. High based storms capable of damaging wind gusts and hail are possible over the area this afternoon as modest CAPE develops over the region. This morning's CAMs show some activity developing later this afternoon and evening.

Stronger wave/upper low moves in for Sunday from the PNW and grazes the CWA. Modest CAPE will once again fuel high based convection over the CWA Sunday afternoon. Again, the main hazards with any storms that develop will be damaging wind gusts and hail. Low forecast confidence in storms developing as optimal forcing and moisture will be located to the north and west of the CWA.

Broad ridging will continue over the central US with trof over the western US. The CWA will sit under southwest flow, keeping conditions warm (highs in the 80s to 90s) with near daily chances for afternoon storms to close out the month. There are some fire weather concerns for the end of this weekend into early next week, mainly over northeastern WY into far southwestern SD. More details in the fire weather discussion.

AVIATION

(For the 00Z TAFS Through 00Z Sunday Evening) Issued At 527 PM MDT Sat Aug 29 2026

Generally expect VFR conditions at the TAF sites through the period. The caveat to this will be isolated to scattered small storms in the region this evening. Have kept PROB30s for TS at both sites this evening, with winds being the main threat of any storms. Transient MVFR/IFR conditions also possible around any heavier precipitation, mostly for vsby. Outside of thunderstorms, SCT to BKN high-level clouds will continue to stream across the region throughout the period.

FIRE WEATHER

Issued At 1105 AM MDT Sat Aug 29 2026

Near-critical to locally critical fire weather conditions may form over Weston County into southwestern SD on Sunday afternoon. Breezy westerly winds will develop by the afternoon with sustained winds of 20 to 25 mph, gusting to 35 to 40 mph. Meanwhile afternoon RHs will range from 15 to 20%. At this time, will hold off on issuing any fire weather headlines due to low confidence in coverage and duration of any critical fire weather conditions.

Fire weather concerns will continue into early next week as hot and mostly dry conditions continue across the area. Main areas of concern will be over northeastern WY into southwestern SD where afternoon humidities will drop into the teens to low 20s.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.